Abstract: Age-related Macular Degeneration (AMD) is the major cause of vision loss after age 50 in the United States. Although an important association of the complement cascade with AMD has recently been made, we still do not understand the pathogenesis of the disease. AMD is characterized by loss of the retinal pigment epithelium (RPE) within the macula (i.e., the center of the retina), and in turn, loss of the overlying foveal photoreceptors. Since RPE and photoreceptors can both be generated from stem cells using cell culture, there is hope for future cell replacement therapy. But, aging changes in Bruch's membrane, the scaffold on which the RPE are anchored, may complicate such therapy, and require surgical repair of Bruch's membrane to provide a suitable environment for cell survival and function. We have referred to such a multipronged approach of surgical reconstruction of the macular architecture in conjunction with cell transplantation as Maculoplasty. ... Read more

Abstract: Increasing evidence suggests an important role for programmed cell death (PCD) pathways in aging phenotypes across species. PCD is critical to the homeostasis of tissues maintained by cell division, for example, the blood and the lining of the gut. During aging, accumulated cellular damage and non-optimal systemic signaling can cause too little cell death (hyperproliferation and cancer), or too much cell death (tissue atrophy and ectopic cell death), thereby limiting tissue function and life span. For these reasons PCD pathways are promising targets for interventions in aging and aging-related diseases: reactivation of PCD may be beneficial in clearing cancerous and senescent cells, whereas inhibiting PCD may help prevent muscle atrophy and nervous system degeneration. ... Read more

Abstract: The APOE ε4 allele is associated with risk of late-onset Alzheimer's disease (AD). Longitudinal memory decline in asymptomatic APOE ε4 carriers shows greater acceleration compared with non-carriers, with a possible allele-dose effect, and begins prior to age 60. These results correlate with imaging and neuropathological studies that show AD-like changes at this age and collectively support the existence of a presymptomatic stage of AD. ... Read more

Abstract: In general, cancer incidence increases with age. However some cancers, such as breast cancer, become indolent in the aged women due to both the "seed" (well differentiated cancer cell) and "soil" (reduced production of estrogen - growth factor for breast cancer cells) effects. Prevention and treatment of cancer in an aged population are discussed. ... Read more

Abstract: Cancer incidence rate was observed to be accelerating or even paradoxically declining among the oldest ages. This seemingly unlikely and contradictory phenomenon is possibly due to the "somatic aging" process. Aging slows down the rates of metabolism, cell proliferation, and so on. The slower-than-normal pace of accumulation of mutations and slower rate of blood-vessel formation (angiogenesis) reduce the occurrence and growth of cancer. ... Read more

Abstract: A higher metabolic rate and elevated oxidative stress levels have been thought of as the primary factors in the aging process. Authors described a new hypothesis for determining longevity - the metabolic stability theory, which states that the extent of the fluctuation in the metabolic rate and how quickly a species returns to the "normal" metabolic rate after extraordinary events affects the organism's longevity the most. ... Read more

Abstract: Apoptosis, or programmed cell death, plays a key role in the development, execution, and maintenance of immune functions. The dynamics of survival of subsets of T lymphocytes with the backdrop of human aging is discussed. ... Read more

Abstract: Typical cells are subject to the fate of replicative senescence -- a key mechanism of our aging process. Cancer cells and, to a certain extent, immune cells have a mechanism to replenish the lost sequence of the telomere and allow them to divide without the usual constraints of replicative senescence. ... Read more

“Angiogenesis inhibitors do far more than simply ‘deprive a tumor of oxygen.’ They inhibit vascular leakage in a tumor, inhibit endothelial nitric oxide synthase, downregulate expression of HIF-1α, upregulate expression of an inhibitor of HIF-1α, upregulate thrombospondin and downregulate plasmin production, to name just a few activities.”

Mark W. Kieran, Judah Folkman, and John Heymach in correspondence to Nature Medicine (9:1104, 2003), in response to a question that angiogenesis inhibitors might promote cancer metastasis.

“The digital information in genomes operates across three diverse time spans: evolution (tens to millions of years), development (hours to tens of years), and physiology (milliseconds to weeks). ... Read more

Dr. David Sinclair and his colleagues at BIOMOL Research Labs, Inc., Plymouth Meeting, PA and the Harvard Medical School, Boston, MA have identified several naturally occurring compounds which can extend the life of yeast cells by 70% and protect, to certain extent, cultured human cells exposed to radiation (Howitz, K.T. et al., Nature 425:191-196, Sep. 11, 2003).

These compounds belong to a chemical group called polyphenols, known for their presence in grapes and red wine. Researchers screened several libraries of compounds and found 17 that could enhance the activity of SIRT1, a human deacetylase that enhances cell survival by deacetylating the ... Read more